Electromagnetic relay



Feb. 28, 1961 wmERG 2,973,464

ELECTROMAGNETIC RELAY Filed Nov. 5, 1958 2 Sheets-Sheet 1 IN vE/VT'OR Ema 14x54 Ml'fl H rroR Mfrs Feb. 28, 1961 E. A. WIBERG 2,973,464

ELECTROMAGNETIC RELAY Filed Nov. 5, 1958 2 Sheets-Sheet 2 United States Patent 2,973,464 ELECTROMAGNETIC RELAY Eric Axel Wiberg, Stockholm, Sweden, assignor to Telefonaktiebolaget L M Ericsson, Stockholm, Sweden, a corporation of Sweden Filed Nov. s, 1958, Ser. No. 771,260

Claims priority, application Sweden Nov. 14, 1957 10 Claims. (Cl. 317-176) The present invention refers to an electromagnetic relay with a magnetizing winding about an iron core and a two-armed L-shaped armature mounted on a relay angle, the lever arms of the armature extending between a bearing device of the armature to the middle of the pole tip of the core, and also to an operating member for the contact springs. Owing to their use for different purposes such telephone relays must be manufactured in different types. These relay types are generally alike with the exception of the lever ratio, which varies due to the required different breakand make-times. In order to reduce the number of different relay types as much as possible, the manufacture of relays with adjustable lever ratios has'been suggested. For instance this has been brought about by making the operating member of the contact springs removable in relation to the springs and the armature. I A move of the operating member interferes, however, with the function of the springs. It has also been suggested to provide an extra lever arm for transmitting the movement of the armature to the operating member such lever arm operates the armature at a displaceable point. To insert such an extra lever arm, however, complicates the construction. According to the present invention a simple and practical'device is obtained by providing armature with different bearing places and by a bearing device arranged to be placed at a suitable bearing place on the relay angle.

The invention will be described more in detail in connection to the enclosed drawings, which in Figs. 1-4 and respectively Figs. -9 show two examples of the application of the invention. Fig. 1 shows in a perspective view an almost complete relay, Figs. 2-4 show details belonging to this relay. Fig. 2 thus shows the armature. Fig. 3 shows the bearing device and Fig. 4 the relay angle. Fig. 5 shows also a relay in a perspective view with another construction of the armature bearing. Figs. 6-9 show details belonging to this relay. Fig. 6 shows the fastening device for the armature. Fig. 7 the armature and Fig. 8 the relay angle. Finally Fig. 9 shows the construction of the bearing device.

The relay shown in Fig. 1 may be of conventional construction except for the armature hearing. The core 11 of the winding is fastened to a relay angle 19, on which the armature 12 is pivotally supported and the contact springs 22 are mounted. Springs 22 are operated by the armature by means of a lifting bar 21. According to the invention the L-shaped armature 12 has on the underside two parallel bearing grooves 14, Fig. 2. As is shown in Fig. l the armature rests on a ledge rising in the left groove from a special bearing device 13, Fig. 3, consisting of an L-shaped iron part. For this position of the armature device 13 the lever-ratio will be 1 to 1.4, i.e. the lengths from the bearing axis to one side to the middle point of the core 11 and to the other side of the lifting bar 21 will be 1 to 1.4. The iron part 13 is fastened by screws 15 in oblong grooves in the relay angle 19, Fig. 4.

2,973,464 Patented Feb. 28, 1961 If the iron part 13, before mounting the armature, is turned degrees in relation to the shown position, so that its rising ledge is on its right side, this ledge will rise in the other right groove of the armature 12, which, however, will have the same position as is shown in Fig. 2 in relation to the relay core and the operating member 21. The lever ratio will now be 1 to 1. By the proposed bearing device it is thus possible to use the relay for two lever ratios without change in the components of the relay.

As the bearing device 13 constitutes a separate component, it can be fastened to the relay angle at each position in such a way that a plane bearing of the armature 12 against the pole surface 11 is obtained. It is made in such a way that before the bearing device 13 is screwed to the relay angle 19, the screws 15 in the oblong holes 20 is displaced to the position, in which a plane bearing is to be obtained. At the adjustment the fastening screws can be loosened somewhat and the winding 10 is connected to a current source so that the armature is operated the plane bearing being controlled. Thereafter the fastening screws 15 are tightened.

The iron part 13, which is the armature bearing, has in the middle of its bearing ledge a rising lug 23, which extends through a slot in the middle of the armature. A lock washer 18 may to be fastened to the lug. The locl; washer has a slot, which corresponds to the lug, and it snaps into two grooves in the lug .23. The lock washer is so placed that the armature cannot become disengaged from its hearing. The lock washer functions also as an attachment for a spring 24, the other end of which is fastened to a clamp 16 bolted to the armature. This spring functions in a known manner to reset the armature to the shown unoperated position when the current is broken by the winding 10.

The relay shown in Fig. 5, apart from the armature bearing, can also be conventionally constructed with core 31 and winding 30, angle armature 32, relay angle 33, and schematically shown spring sets 34 fastened to the relay angle. In this embodiment the armature is not provided with bearing grooves, but it has on the underside a plane bearing surface 41. In Fig. 6 the armature is shown from below. As is shown in this figure the armature is on the underside provided with a plane spring 35, in which there are two oblong opened grooves 36. The armature is fastened by screws 37, which extended through these grooves and through holes 45 of the relay angle 33. The screws are tightened first when the bearing of the armature against the end of the core 31 has been controlled. The armature will then have a fixed position on the relay in relation to the spring sets 34.

In order to provide two different level ratios for the bearing for the armature, there are on the relay angle 33, Fig. 8, two rows of grooves 39 and 40. When the two clamps 42 are placed in the right row 39 of these grooves, as is shown in Figs. 1 and 8, the lever ratio will be 1 to 1. If the two wire clamps are moved to the left groove row 40, the lever ratio will be 1 to 1.4. The construction of the wire clamps is shown in Fig. 9. They have preferably a semicircular section with the roundest surface facing upwards. Of course, another cross-section can be used, for instance a triangular one with an edge straight upwards. For resetting the armature from its operated position against the end of the core 31, a spring 43 is provided which extends between the relay angle 33 and a clamp 44 on the armature.

It has been shown and described how two different lever ratios can be attained by using the same details. Of course, more groove rows 14 respectively 39, 40 than two may be provided and then more than two are lever ratios obtained with one and the same relay.

I claim:

1. A relay device comprising, in combination, an energizable magnetic core, an armature responsive to said core during periods said core is energized, an adjustable fulcrum for carrying said armature thereon with one end thereof in spaced relation with respect to one end of said core, and means for fixedly holding said armature in place on said fulcrum, said fulcrum being positioned for preselecting the travel time of said one end of said armature to said one end of said core.

2. A relay device comprising, in combination, an energizable magnetic core, an armature responsive to said core during periods said core is energized, a mounting surface, supporting means having a fulcrum surface for carrying said armature thereon in spaced relation with revspect to one end of said core, said supporting means being positionable on. said mounting surface for controlling the position of said fulcrum surface with respect to said armature carried thereon, and means fixedly holding said armaturein place on said fulcrum surface, said armature being tiltable on said fulcrum surface to said one end of said core during periods said core is energized, whereby the travel time of said armature to said one end of said core is preselected by the position of said supporting means.

3. A relay device as described in claim 2 wherein said armature is L-shaped and is carried on said fulcrum surface with one arm thereof juxtaposed in spaced relation to said one end of said core.

4. A relay device as described in claim 2 wherein said armature has a grooved surface which mates with said fulcrum surface for carrying said armature thereon.

5. A relay device as described in claim 2 wherein said fulcrum surface is transversely disposed with respect to said armature in any selected position of said supporting means on said mounting surface.

6. A relay device as described in claim 2 wherein said supporting means is reversibly positionable in one of two preselectable positions on said mounting surface for preselecting the spacing between said armature and said core.

7. A relay device comprising, in combination, an energizable magnetic core, an armature having a resilient portion responsive to said core during periods said core is energized, a mounting surface for said armature, said resilient portion being connected to said mounting surface with a surface of said armature spaced from one end of said core, and means fixedly holding said one end of said armature in place in spaced relation to said one end of said core, said armature being tiltable about said resilient portion with the travel time of said one end of said armature to said one end of said core being determined by the position of said resilient portion on said mounting surface.

8. A relay device comprising, in combination, an energizable magnetic core, an armature having a resilient portion disposed on a surface thereof, said armature being responsive to said core during energizable periods of said core, a mounting surface for said armature con nected to said core and disposed substantially parallel thereto, said resilient portion being connected to preselected positions on said mounting surface for control ling the spacing between another surface of said armature and one end of said core, said armature being tiltable about said resilient portion with the travel time of said other surface of said armature to said one end of said core being determined by the position of said resilient portion on said mounting surface.

9. A relay device as described in claim 8 wherein said armature is L-shaped and one arm of which is juxtaposed in spaced relation with respect to said one end of said core.

10. A relay device as described in claim 8 wherein said mounting surface has a plurality of preselected positions thereon for securing said resilient portion thereto to control the travel time of said other surface of said armature to said one end of said core. 

